foo.cc: In function 'int main()':
foo.cc:13:10: warning: comparison of constant '10' with boolean expression is always true [-Wbool-compare]
   13 |   if(1<=x<=10)
      |      ~~~~^~~~
foo.cc:13:7: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
   13 |   if(1<=x<=10)
      |      ~^~~
foo.cc:19:11: warning: comparison of constant '15' with boolean expression is always true [-Wbool-compare]
   19 |    if(10<x<=15)
      |       ~~~~^~~~
foo.cc:19:9: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
   19 |    if(10<x<=15)
      |       ~~^~
foo.cc:25:12: warning: comparison of constant '30' with boolean expression is always true [-Wbool-compare]
   25 |     if(15<x<=30)
      |        ~~~~^~~~
foo.cc:25:10: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
   25 |     if(15<x<=30)
      |        ~~^~
foo.cc:5:8: warning: unused variable 'y' [-Wunused-variable]
    5 |  int x,y;
      |        ^

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